The Information Management Core has service and development components. The Information core will provide statistical and data management support for all projects, and will enter, verify, and maintain the clinical assessment. Many of our projects face formally similar statistical problems. We will develop innovative methodological approaches to three of these common problems: 1) Estimating missing data when the probability of response depends on the missing values; 2) Combining within-person and between-person statistical models for time series data; and 3) Using structural equation models to rule out interpretational confounding among measured constructs in correlational studies. By emphasizing common statistical approaches to formally similar problems, the information core will provide statistical quality control, integrate diverse substantive projects, and enhance the coherence of the program by providing a statistical dimension of organization.